Decline in net primary productivity caused by severe droughts: evidence from the Pearl River basin in China

Abstract

Understanding the spatiotemporal characteristics of drought events and their impacts on terrestrial net primary productivity (NPP) is crucial for drought mitigation and environmental protection. This study, by taking the Pearl River basin as the case region, investigated drought duration, severity, intensity, affected area, and centroids during 1960–2015 based on the Standardized Evapotranspiration Deficit Index and three-dimensional clustering algorithm and then revealed how these drought characteristics have affected NPP. Results showed that there were altogether 32 severe drought events lasting at least 3 months in the basin, with half lasting longer than 6 months. The total NPP loss significantly correlated with drought severity and intensity. Most drought events caused reduce in NPP across more than half of the drought-affected area; specifically, the February–December drought in 2011 has cut NPP by 31.85 Tg C, accounting for 11.7% of the regional annual mean NPP, while the September 2009–September 2010 drought caused a decrease of 20.26 Tg C in NPP. Our research improves the insight into the relationship between NPP and drought, which helps decision-makers manage droughts and provides guidance for drought-related studies across other regions.

Exploring the Potential of Solar-Induced Chlorophyll Fluorescence Monitoring Drought-Induced Net Primary Productivity Dynamics in the Huang-Huai-Hai Plain Based on the SIF/NPP Ratio

“…Drought events are an important factor causing losses in vegetation NPP. Many studies have investigated the impact of drought on NPP, showing that drought can cause severe losses in NPP [65]. However, real-time monitoring of drought-induced dynamic changes in NPP is difficult, as large-scale NPP data cannot be obtained in real time.…”

“…Our study comprehensively analyzed the relationship between SIF and NPP during two long-term drought events in the HHH Plain at various aspects and scales, discussing and demonstrating the potential of SIF for monitoring dynamic changes in NPP induced Drought events are an important factor causing losses in vegetation NPP. Many studies have investigated the impact of drought on NPP, showing that drought can cause severe losses in NPP [65]. However, real-time monitoring of drought-induced dynamic changes in NPP is difficult, as large-scale NPP data cannot be obtained in real time.…”

Comprehensive evaluation of vegetation responses to meteorological drought from both linear and nonlinear perspectives

“…The Pearl River Basin (PRB), which is of great significance for socio-economic development of China, has become the major source of carbon dioxide emissions in China (Zhang et al, 2015). As the PRB is located in a humid area, it has a complex vegetation ecosystem, which is of great significance for local biological carbon sequestration to partially offset fossil fuel emissions (Zhou and Zhou, 2021). However, Deng et al (2018) showed that both drought frequency and severity increased in the PRB, which might weaken the absorption of carbon by vegetation.…”